Numerical simulation showed that LVAD intervention significantly increased blood flow velocity, wall shear stress, and vorticity density in the ascending aorta compared to the heart failure condition, improving hemodynamics to resemble a healthy state.
Does LVAD intervention improve aortic hemodynamics and vorticity flow in a computational model of a heart failure patient?
Computational fluid dynamics simulation shows that LVAD support in a heart failure model restores aortic vorticity intensity to levels similar to a healthy heart, which may help prevent flow separation and atherosclerosis.
Ventricular assist devices have been widely used and accepted to treat patients with end-stage heart failure. The role of VAD is to improve circulatory dysfunction or temporarily maintain the circulatory status of patients. In order to be closer to the medical practice, a multi-Domain model of the left ventricular coupled axial flow artificial heart was considered to study the effect of its hemodynamics on the aorta. Because whether LVAD itself was connected between the left ventricular apex and the ascending aorta by catheter in the loop was not very important for the analysis of simulation results, on the premise of ensuring the multi-Domain simulation, the simulation data of the import and export ends of LVAD were imported to simplify the model. In this paper, the hemodynamic parameters in the ascending aorta, such as blood flow velocity vector, wall shear stress distribution, vorticity current intensity, vorticity flow generation, etc., have been calculated. The numerical conclusion of this study showed the vorticity intensity under LVAD was significantly higher than that under patients' conditions and the overall condition is similar to that of a healthy ventricular spin, which can improve heart failure patients' condition while minimizing other pitfalls. In addition, high velocity blood flow during left ventricular assist surgery is mainly concentrated near the lining of the ascending aorta lumen. What's more, the paper proposes to use Q criterion to determine the generation of vorticity flow. The Q criterion of LVAD is much higher than that of patients with heart failure, and the closer the LVAD is to the wall of the ascending aorta, the greater the Q criterion is. All these are beneficial to the effectiveness of LVAD in the treatment of heart failure patients and provide clinical suggestions for the LVAD implantation in clinical practice.
Gao et al. (Thu,) は心不全に関する他の研究を実施しました (n=1)。左心室補助装置 (LVAD) と LVAD のない心不全患者および健康な人間の間で、血行動態パラメータ（血流速度、壁剪断応力、渦度密度）が評価されました。数値シミュレーションにより、LVAD介入が心不全の状態と比較して胸部大動脈の血流速度、壁剪断応力、渦度密度を有意に増加させることが示され、血行動態が健康な状態に似るように改善されました。